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<pre>
      SUBROUTINE <a name="SLAR2V.1"></a><a href="slar2v.f.html#SLAR2V.1">SLAR2V</a>( N, X, Y, Z, INCX, C, S, INCC )
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  -- LAPACK auxiliary routine (version 3.1) --
</span><span class="comment">*</span><span class="comment">     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
</span><span class="comment">*</span><span class="comment">     November 2006
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     .. Scalar Arguments ..
</span>      INTEGER            INCC, INCX, N
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">     .. Array Arguments ..
</span>      REAL               C( * ), S( * ), X( * ), Y( * ), Z( * )
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  Purpose
</span><span class="comment">*</span><span class="comment">  =======
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  <a name="SLAR2V.17"></a><a href="slar2v.f.html#SLAR2V.1">SLAR2V</a> applies a vector of real plane rotations from both sides to
</span><span class="comment">*</span><span class="comment">  a sequence of 2-by-2 real symmetric matrices, defined by the elements
</span><span class="comment">*</span><span class="comment">  of the vectors x, y and z. For i = 1,2,...,n
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     ( x(i)  z(i) ) := (  c(i)  s(i) ) ( x(i)  z(i) ) ( c(i) -s(i) )
</span><span class="comment">*</span><span class="comment">     ( z(i)  y(i) )    ( -s(i)  c(i) ) ( z(i)  y(i) ) ( s(i)  c(i) )
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  Arguments
</span><span class="comment">*</span><span class="comment">  =========
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  N       (input) INTEGER
</span><span class="comment">*</span><span class="comment">          The number of plane rotations to be applied.
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  X       (input/output) REAL array,
</span><span class="comment">*</span><span class="comment">                         dimension (1+(N-1)*INCX)
</span><span class="comment">*</span><span class="comment">          The vector x.
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  Y       (input/output) REAL array,
</span><span class="comment">*</span><span class="comment">                         dimension (1+(N-1)*INCX)
</span><span class="comment">*</span><span class="comment">          The vector y.
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  Z       (input/output) REAL array,
</span><span class="comment">*</span><span class="comment">                         dimension (1+(N-1)*INCX)
</span><span class="comment">*</span><span class="comment">          The vector z.
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  INCX    (input) INTEGER
</span><span class="comment">*</span><span class="comment">          The increment between elements of X, Y and Z. INCX &gt; 0.
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  C       (input) REAL array, dimension (1+(N-1)*INCC)
</span><span class="comment">*</span><span class="comment">          The cosines of the plane rotations.
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  S       (input) REAL array, dimension (1+(N-1)*INCC)
</span><span class="comment">*</span><span class="comment">          The sines of the plane rotations.
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  INCC    (input) INTEGER
</span><span class="comment">*</span><span class="comment">          The increment between elements of C and S. INCC &gt; 0.
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">  =====================================================================
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     .. Local Scalars ..
</span>      INTEGER            I, IC, IX
      REAL               CI, SI, T1, T2, T3, T4, T5, T6, XI, YI, ZI
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">     .. Executable Statements ..
</span><span class="comment">*</span><span class="comment">
</span>      IX = 1
      IC = 1
      DO 10 I = 1, N
         XI = X( IX )
         YI = Y( IX )
         ZI = Z( IX )
         CI = C( IC )
         SI = S( IC )
         T1 = SI*ZI
         T2 = CI*ZI
         T3 = T2 - SI*XI
         T4 = T2 + SI*YI
         T5 = CI*XI + T1
         T6 = CI*YI - T1
         X( IX ) = CI*T5 + SI*T4
         Y( IX ) = CI*T6 - SI*T3
         Z( IX ) = CI*T4 - SI*T5
         IX = IX + INCX
         IC = IC + INCC
   10 CONTINUE
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     End of <a name="SLAR2V.83"></a><a href="slar2v.f.html#SLAR2V.1">SLAR2V</a>
</span><span class="comment">*</span><span class="comment">
</span>      RETURN
      END

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